Inner bag for bag-in-box

ABSTRACT

An inner bag for bag-in-box capable of increasing an easiness in handling and convenience when a filled inner bag ( 1 ) for bag-in-box is handled without an outer box, where reinforced heat sealed parts ( 5, 5′ ) formed by cutting out side films ( 4, 4′ ) and sealing a front film ( 6 ) with a rear film are provided continuously or closely to heat sealed parts ( 2, 3 ) on an upper side on/or a lower side of the inner bag, or a holding part is provided formed by sealing the front film ( 6 ) with the rear film through or without through the side films ( 4, 4′ ) so that a not sealed part ( 17 ) between the side films ( 4, 4′ ) is formed at or near at least one corner part between the films and the heat sealed parts ( 2, 3 ) and so that, when a hand is accessed to the outside of the inner bag ( 1 ) through the not sealed part ( 17 ).

FIELD OF THE INVENTION

[0001] The present invention relates to an improvement for handling ofinner bag for bag-in-box comprising an inner bag which is a moldedproduct made of synthetic resin film and an outer box made of cardboard.More in detail, the present invention relates to an improved inner bagfor bag-in-box possessing a gazette part.

BACKGROUND OF THE INVENTION

[0002] In general, a container composed of an inner bag fabricated byheat sealing of synthetic resin film and an outer box made of cardboardwhich is prepared for the purpose of filling up, preserving andtransferring of fluid such as liquid or powder is commonly called as abag-in-box, and ones whose capacity are from 5 to 20 liter are broadlyused as a container for foods or medicines. These containers are mainlyapplied for the business use, and actually used as a container formaterials of foods or medicines or as a large size container forsubdivisional use.

[0003] In the meanwhile, recently, for the purpose of severe sanitarycontrolling of producing environment of foods or medicines, therequirements to protect the contamination of the producing environmentby dusts generated from the outer box by picking out an inner bag fromthe outer box and carrying it alone in into the producing environment isbecoming more serious.

[0004] Therefore, for these inner bag for bag-in-box, the easiness inhandling when handled without outer box is becoming strongly required.

[0005] In the meanwhile, these inner bags for bag-in-box are becoming tobe required to have a good handling efficiency when handled without anouter box.

[0006] The inner bag for bag-in-box can be classified into following twotypes. That is, one is a molded type inner bag having excellentself-standing ability prepared by a blow molding method or by a vacuummolding method and another one is a film type inner bag which isprepared by thermally sealing of film which is characterized by usingsmaller amount of synthetic resin. Further, said film type can beclassified into a plane bag type and a gazette bag type.

[0007] Although the self-standing ability of the above mentioned gazettetype inner box as a container is not superior to that of a molded type,it is superior to that of a plane bag type, therefore, it is desirablyused as the inner bag to be handled without an outer box.

[0008] But, the gazette type bag-in-box has several problems, and theintensity of it is pointed out as one of the problems.

[0009] For example, in Japanese utility model laid open publicationJP64-9174 (refer to drawing No.7), a gazette type bag-in-box whosegazette part is formed by folding both sides of periphery edge of thebag main-body to inner side is disclosed.

[0010] As disclosed in said Japanese utility model laid open publicationJP64-9174, a bag of gazette shape has following defect. That is, whenthe bag is filled up by liquid, since the stress is concentrated to thecrossing point of crease of folding part of film located to the sidesurface and a heat sealed part of upper or lower side, the bag is weakagainst the stress such as inner pressure.

[0011] In above mentioned Japanese utility model laid open publicationJP64-9174, for the purpose to improve above mentioned defect, there isthe description that the intensity of the crossing point is improved bypreparing an oblique belt shape heat sealed part which traverses fromthe crossing point of crease of folding part and a heat sealed part ofupper or lower side to the voluntary point of the both sides ofperiphery edge of the bag. The preparation of said oblique belt shapeheat sealed part is also useful from the view point to reduce theremaining amount of liquid at the discharging of the liquid, because itis effective to prevent the liquid from remaining between a film and afilm at the end of inner bag.

[0012] However, the effect of preparation of the oblique belt shape heatsealed part is not sufficient. Sometimes, by the strong impact such asfalling down, the bag is broken because of lack of intensity. Accordingto the description of above mentioned Japanese utility model laid openpublication JP64-9174, the effect of the improvement is only illustratedas follows. Namely, since the tensile tension is dispersedhomogeneously, it is possible to use a press discharging methodcharacterizing by discharge the contents by pressing the outer surfaceof the bag. Further, the triangle part locating at the outside ofoblique belt shape heat sealed part is easily opened at the handling ofa filled up bag and deteriorate the intensity of above mentionedcrossing point.

[0013] Furthermore, this triangle part disturbs the easiness in handlingof the filled up bag, when it is contained into an outer box.

[0014] Still further, since this triangle part becomes hard and disturbsthe self-standing ability of the bag, said triangle part becomes thecause to disturb the self-standing of the filled up inner bag when it ishandled without outer bag.

[0015] By the way, in above mentioned Japanese utility model laid openpublication JP64-9174, there is a description to cut off the triangleparts of the lower part of the inner bag for the purpose to improve theself-standing ability of it. However, when the triangle part is cut off,the new problems, that the crossing point becomes more easily opened andthe intensity to the inner pressure is affected, are arisen. Such kindof problems can be observed when a laminated film prepared by laminatingmulti layers so as a biaxial orientated film or a nylon resin layerwhich are hard to be adhered by heat sealing to be arranged at thesurface. And, for the improvement of the intensity of gazette typebag-in-box inner bag, above mentioned problem is an obstacle to disturbsaid improvement.

[0016] Further, another problem is pointed out. Namely, since anadequate hand hold part is not attached to the inner bag, the handlingof it is not so easy, especially when a filled up inner bag is picked upand removed from an outer box or is carried without outer box. For thepurpose of easiness in handling of an inner bag, as shown in FIG. 21,the inner bag for bag-in-box to which a hand hold is attached isdisclosed in Japanese Patent Laid Open Publication 2-8763. In this case,a heat sealed part is formed on the upper part of gazette type innerbag, and further a heat sealed part is formed so as a front film and arear film become one body at the corner part of the inner bag. And saidheat sealed part can be held by a hand. However, according to saidreference invention, since whole upper side of the bag is sealed by heatin a straight line at the forming process of a heat sealed part of thecorner part, there is no space to thrust a finger into. Therefore, theproblem that the heavy load is burdened with a finger is pointed out.

[0017] Additionally, at the filling up process, in a case when an innerbag is set to an outer box after contents are filled up into the innerbag, there is also a problem same as mentioned above.

DISCLOSURE OF THE INVENTION

[0018] The structural feature of a gazette shape inner bag forbag-in-box is characterized as that the side film which is folded fromboth side edge part to inner side is inserted between a front film and arear film at the gazette part. A heat sealed part of an upper or lowerside is consisted of two heat sealed parts. That is, one is the heatsealed part locating at the center position where the front film and therear film are faced and said front film is adhered with said rear filmdirectly by heat sealing (this part is called as a heat sealed part),and another one is the heat sealed part locating to the outer side wherethe front film or the rear film is adhered with the side film by heatsealing. At the preparation of the heat sealed part of upper side orlower side, said two heat sealed part are prepared continuously to forma straight line. Generally, the surface and the reverse surface of thefilm which consist of a gazette shape inner bag for bag-in-box areusually made of thermo fusable film, and the films of the side surfaceare sealed by heat and adhered each other at the folded part of upper orlower side. In a case when a laminated film prepared by laminating multilayers so as a biaxial orientated film or a nylon resin layer which arehard to be adhered by heat sealing to be arranged at the surface isused, for the purpose to improve the intensity of inner bag, films ofthe side surface are not sealed by heat and not adhered each other.

[0019] The present invention is carried out to dissolve above mentionedproblem that a conventional bag-in-box has. The first object of thepresent invention is to improve the intensity of the inner bag withoutspoiling the self-standing ability of it when a filled up inner bag forbag-in-box is handled without an outer box. The second object of thepresent invention is to provide an inner bag for bag-in-box whoseeasiness in handling and convenience are improved.

[0020] The first invention is the invention which is preferable to beapplied to a gazette shape inner bag for bag-in-box whose side film tobe folded is composed of a laminated film prepared by laminating multilayers so as a resin layer which is hard to be adhered by heat sealingis arranged at the surface. The important point of the first inventionis an inner bag for bag-in-box comprising reinforcing heat sealed partsformed by cutting out side films and sealing a front film with a rearfilm are provided continuously or closely to heat sealed parts on anupper side and/or a lower side of the inner bag. In a case of abovementioned inner bag for bag-in-box, it is desirable that the front filmis adhered by heat sealing with the rear film by cutting out the sidefilms at a corner part or near the corner part. In a case of abovementioned inner bag for bag-in-box, it is further desirable to dividethe containing part for contents by heat sealed part so that forms finparts of triangle shape. At least one of said fin parts of triangleshape can be cut off, and it is desirable to cut off all fin parts oftriangle shape locating at the lower part.

[0021] The inner bag for bag-in-box to which a reinforcing heat sealedparts formed by sealing a front film with a rear film are provided hasfollowing strong points based on above mentioned structural feature,that is;

[0022] (1) At the heat sealed part on an upper side or a lower side ofthe gazette shape inner bag for bag-in-box, a front film is adhered byheat seal with a rear film by cutting out side films, and when abnormalstress caused by careless falling down of the inner bag is loaded to thebag, the breaking of the side films near the heat sealed part on anupper side or a lower side is prevented by this structural feature, andfurther the load burdened to the top heat sealed part can be reduced.

[0023] (2) Further, at the corner part or near the corner part, sidefilms are cut off and a front film is adhered by heat sealing with arear film, and by this structural feature, the reinforcing effectdescribed in (1) becomes more remarkable and the damage of a side filmcaused by the contact with the inner surface of an outer box can beprevented. And, since the heat sealed parts at the corner part can beused as the holding part, it is convenience for loading and unloading ofthe filled up inner bag from the outer box, transferring of the filledup inner bag or for discharging of the contents contained in the innerbag.

[0024] (3) The amount of the remaining liquid after whole contents inthe inner bag is discharged can be reduces by making the inner baggazette shape having fin parts divided from the containing part by theheat sealed part. And at the forming process of a reinforcing heatsealed part, even if the cutting off width of a side film is wider thanthe width of an upper or lower heat sealed part, the cut out part isexisting in the fin part, and the leaking of the contained liquid doesnot occur.

[0025] (4) And, in a case when the film composing an inner bag is a hardmaterial, since the presence of the fin part prevents easiness inhandling at insertion of the filled up inner box into an outer box, atputting on the lid and further deteriorates the self standing ability ofthe bag, it is desirable to cut off the fin part previously to avoidsuch kinds of inconvenience.

[0026] The second invention is the invention which is desirable to beapplied to a gazette shape inner bag for bag-in-box prepared by adhesionby heat sealing of one or more sheets of film and the important point ofthe invention is illustrated as follows. That is, the important point ofthe second invention is an inner bag for bag-in-box providing a holdingpart formed by sealing the front film with the rear film through orwithout through the side film so that a not sealed part between thefilms is formed at or near at least one corner part between the filmsand the heat sealed parts and so that, when a hand is accessed from theside part of the inner bag, fingers are passed to the outside of theinner bag through the not sealed part. For the purpose of furtherimprovement of the easiness in handling and convenience of the inner bagfor bag-in-box, it is desirable that the holding part is prepared onboth side of the heat sealed part locates at upper and/or lower side.Furthermore, it is more desirable to provide a cut out part prepared bycutting off one part or all part of film of above mentioned not sealedpart locating at upper and/or lower side, because the load to beburdened with a finger can be reduced when the bag is held by a hand.Still further, it is desirable to prepare a band shape sealed part atthe voluntary position from the edge of the heat sealed part locating atupper and/or lower side to the outer periphery part, prepare a fin partdivided by triangle shape and provide a holding part to the triangle finpart. Said triangle fin part which locates at the lower side can be cutoff, and by cutting off it, the self standing ability of the inner bagwhen it is handled without an outer box can be improved.

[0027] In the case of the gazette shape inner bag of the presentinvention, the front film is adhered by heat sealing with the rear filmso that a not sealed part is formed at or near at least one cornerbetween the heat sealed part. The inner bag is designed so as the fingercan pass through from the not sealed part of the front film and the rearfilm when a hand is accessed from the side part of the inner bag to thegap between the front film and the side film or the rear film and theside film. Therefore, the bag can be held by hand without burdening theload to fingers. And it is desirable to provide a holding part composedof the heat sealed part of the front film with the rear film to the bothside of the heat sealed part so as the inner bag can be held by bothhands.

[0028] When a single film or a multi layered film which has a heatadherent resin layer such as polyethylene or polypropylene on the bothsurfaces is used alone as the side film, the front film and the rearfilm can be adhered by heat sealing through side film at the cornerpart. Therefore, for the purpose to form a not sealed part of sidefilms, it is only needed to seal with a seal bar used for the sealing ofupper or lower side possessing a cut out to form a not sealed part. Whena laminate which is prepared so as a resin layer that is hard to beadhered by heat seal such as a polyamide resin layer or a biaxialorientated film to be arranged on the surface is used as the side film,for the purpose to adhere a front film with a rear film by heat seal, apart of the side film is cut off by circular or oval shape (punch hole)and the reverse side of the front film is adhered by heat seal with thereverse side of the rear film without through the side film. It isdesirable to prepare plural punch holes to improve the intensity, andpreferably, the distance among punch holes can be make wider and make ita not sealed part so as to allow the insertion of fingers.

[0029] As mentioned above, easiness in handling of the inner bag of thepresent invention can be improved by forming a holding part prepared byadhering the front film with the rear film by heat seal so as to form anot sealed part between at least one corner part and heat sealed part,and said not sealed part is located at the corner part or near thecorner part. However, when the amount of the contents is over than 10litter, films of higher intensity is used and the toughness of the innerbag becomes stronger. Therefore, when a filled up inner bag is picked upby holding a holding part, the film at the not sealed part is benttoward inner side and sometimes a finger is caught between films. Toreduce the load to the finger, in the present invention, for example, anot sealed part is prepared on upper or lower side and prepare a cut outpart in a part of said not sealed part. Throughout the cut out part,fingers can pass through and can hold the holding part provided to upperor lower side. And by above mentioned structural feature, the handlingof the inner bag becomes very easy, that is, easiness in handling, forexample, picking out the inner bag from the outer box, carrying theinner bag or discharging the contents from the inner bag is improved.Further, also the work to insert the inner bag filled up with thecontent to the outer box becomes very easy. By preparing a cut out part,a hole is prepared on upper or lower side, and hereinafter this cut outpart can be described as a handle hole. Surrounding the handle hole, thenot sealed part can be remained or can not be remained. In a case thatthe not sealed part is not remained, a hole is formed after all side issealed by heat and the hole can be used as a handle hole.

[0030] In the present invention, for the purpose to prevent the leak ofthe contents in the inner bag which is caused by preparing the cut outpart, it is desirable to prepare a band shape heat sealed part at thevoluntary position from the edge of a heat sealed part locating at upperand/or lower side to an outer periphery part, and prepare a fin partdivided by triangle shape. And by providing a holding part to thetriangle fin part, the contents do not remain in the corner part at thedischarging operation, further it acts as a protector of the side filmat the transferring operation of the filled up bag-in-box. Further, bycutting off the triangle shape fin part located at the lower side, theself standing stability of the inner bag, which is important when theinner bag is took out, is improved so that the inner bag is easilycontained in the outer box.

[0031] The gazette shape inner bag for bag-in-box of the presentinvention is the gazette shape bag prepared by inserting a side filmwhich is folded to inner side between the front film and rear film andwhose surrounding part is sealed by heat and having tucks at the sidepart, however, it is possible to use a cylinder shape film instead ofthe front film, rear film and the side surface film, both sides of thecylindrical film are fold to inner side, and to adhere the upper cornerpart with the lower corner part by heat sealing without forming a heatsealed part on a side part.

BRIEF ILLUSTRATION OF THE DRAWINGS

[0032]FIG. 1 is the plane view of the folded state of one example of theinner bag for bag-in-box of the first invention.

[0033]FIG. 2 is the plane view of the folded state of the other exampleof the inner bag for bag-in-box of the first invention.

[0034]FIG. 3 is the plane view from the bottom of the inner bag forbag-in-box of FIG. 2 in which liquid filled up.

[0035]FIG. 4 is the plane view of the other example of the inner bag forbag-in-box of the first invention.

[0036]FIG. 5 is the plane view from the bottom of the inner bag forbag-in-box of FIG. 4 in which liquid is filled up.

[0037]FIG. 6 is the plane view of the other example of the inner bag forbag-in-box of the first invention.

[0038]FIG. 7 is the example of the conventional gazette shape inner bagfor bag-in-box on which oblique heat sealed parts are formed.

[0039]FIG. 8 is the example of the conventional gazette shape inner bagfor bag-in-box from which the outside parts from oblique heat sealedparts are cut off.

[0040]FIG. 9 is the plane view from the bottom of the inner bag forbag-in-box of FIG. 7 in which liquid contents is filled up.

[0041]FIG. 10 is the plane view from the bottom of the inner bag forbag-in-box of FIG. 8 in which liquid is filled up.

[0042]FIG. 11 is the plane view of the folded state of one example ofthe inner bag for bag-in-box of the second invention.

[0043]FIG. 12 is the plane view of the folded state of the other exampleof the inner bag for bag-in-box of the second invention.

[0044]FIG. 13 is the plane view of the folded state of the other exampleof the inner bag for bag-in-box of the second invention to which cut outparts are formed.

[0045]FIG. 14 is other example of the inner bag for bag-in-box of thesecond invention showing the plane view of the folded state of the innerbag for bag-in-box of FIG. 13 from which triangle fin parts locating atlower position are cut off.

[0046]FIG. 15 is the perspective view of the inner bag for bag-in-box ofFIG. 14 in which liquid is filled up.

[0047]FIG. 16 is the other example of the inner bag for bag-in-box ofthe second invention showing the plane view of the folded state of theinner bag to the corner part of which a punch hole is formed.

[0048]FIG. 17 is the other example of the inner bag for bag-in-box ofthe second invention showing the plane view of the folded state of theinner bag which abbreviate to form a heat sealed part at the both sides.

[0049]FIG. 18 is the other example of the inner bag for bag-in-box ofthe second invention which abbreviates to form a heat sealed part at thesides, showing the plane view of the folded state of the inner bag.

[0050]FIG. 19 is the partial plane view of the other example of theinner bag for bag-in-box of the second invention showing the foldedstate of the inner bag to the corner part and near the heat sealed partof which punch holes are formed.

[0051]FIG. 20 is the partial plane view of another example of the innerbag for bag-in-box of the second invention showing the folded state ofthe inner bag to the corner part and near the heat sealed part of whichpunch holes and also cut out parts are formed.

[0052]FIG. 21 is the conventional inner bag for bag-in-box with handleparts.

THE BEST EMBODIMENT TO CARRY OUT THE INVENTION

[0053] The present invention is illustrated more in details.

[0054] As the materials of the bag used in the first invention, alaminate such as a laminated film or a co-extruded film is usedaccording to the required ability. As a laminate to be used, a laminatehaving following structural feature can be mentioned. That is, a filmhaving relatively high mechanical strength such as biaxial orientatedpolyamide, biaxial orientated polyester or biaxial orientatedpolypropylene or a resin layer not to be easy sealed by heat e.g.polyamide resin layer is arranged to be the outermost surface layer, anda polyolefin resin layer to be easily sealed by heat such aspolyethylene or polypropylene is arranged to be the inmost layer, can bementioned. When it is necessary to add further ability to theselaminate, an adequate functional film can be voluntarily added to thelaminate. For example, when a barrier ability against oxygen gas isnecessary, a silica evaporated film or copolymer ofethylene-vinylalcohol (EVOH) can be added, and when a light shieldingability is necessary, an aluminum foil or an aluminum evaporated filmcan be added to the laminate. That is, adequate multi layered film,which is a laminate, is voluntarily selected according to the use. Forexample, a laminate film composed of polyester, aluminum foil andpolyethylene, a co-extruded multi layered film of EVOH and polyethyleneor a co-extruded multi layered film of polyamide, EVOH and polyethylenecan be mentioned. Further, these films can be used alone or can be usedby overlapping with polyethylene single film without sealing, however,not intending to be limited to them.

[0055] In the present invention, the heat sealed part of upper and/orlower side indicates the part where a front film is directly adhered byheat seal with a rear film at upper and/or lower side. In the presentinvention, a cut out part is prepared to a side film continuously orclosely to said heat sealed part, and a reinforced heat sealed part isformed by adhering a front film with a rear film by heat sealing. As theshape of the cut out part, any shape such as circular or oval shape canbe used, and for the purpose to improve the mechanical strength pluralnumbers of cut out parts can be prepared. In this case, it is desirableto prepare a cut out part on the corner part or closely to the cornerpart.

[0056] Still further, it is desirable to provide a heat sealed part atthe position from the edge part of heat sealed part locating at upperand/or lower side toward the side periphery part, and to divide thecontaining part for contents by said heat sealed part, because theamount of remaining liquid can be reduced by dividing the containingpart. And, it is further desirable by the reason mentioned above to cutoff and remove the triangle shape fin parts that is divided by said heatsealed parts.

[0057] The first invention will be illustrated more readily accordingwith the drawings.

[0058]FIG. 1 is the plane view of the folded state of one example of theinner bag for bag-in-box of the first invention.

[0059] In FIG. 1, 1 is an inner bag, 2 is a heat sealed part of theupper side, 3 is a heat sealed part of the lower side, 4, 4′ are sidefilms which are folded, 5, 5′ are reinforcing heat sealed parts whichexist closely to the heat sealed part of the upper side, 6 is a frontfilm of the inner bag and 7 is a heat sealed part which divides acontaining part and a fin part. By preparing holes previously to eachfolded side films 4, 4′, and by sealing lower side, the reinforce heatsealed part is formed by adhering the front film with the rear film byheat sealing at the hole position. And, in the drawings, 8 and 10 are acrossing point of the heat sealed part of the lower side and the sidefilm, 9 and 11 are crossing point of the heat sealed part of the upperside and the side film, 13 is a heat sealed part of the side periphery,14 is a rear film and 15 is a spout.

[0060]FIG. 2 is the case of the inner bag for bag-in-box of FIG. 1 towhich a corner heat sealed part 16 is formed by cutting out the sidefilm near the corner point. FIG. 3 is a plane view from the bottom ofthe inner bag for bag-in-box of FIG. 2 in which liquid is filled up. Inaddition to the reinforced heat sealed part 5, 5′, since the front filmand the rear film of the bag are becoming one body, even if the impactis added, the side film near the heat sealed part does not spread andthe mechanical strength is improved.

[0061]FIG. 4 is the shape showing outer part of the heat sealed part 7which divide a containing part and fin part is cut off.

[0062]FIG. 5 is the perspective illustration from the bottom side of theinner bag for bag-in-box of FIG. 4 in which liquid is filled up. Same asto FIG. 1, a front film and a rear film of inner bag are adhered by heatsealing and become one body at the reinforcing heat sealed parts 5, 5′,therefore, even if the impact is added, the side film near the heatsealed part does not spread and the mechanical strength is improved.Further, the inner bag can stand up by itself stable, because the finpart is cut off.

[0063]FIG. 6 is another example of the present invention. This drawingshows the example that the all fin parts are cut off.

[0064]FIG. 7 and FIG. 8 are the plane view of the conventional inner bagfor bag-in-box. FIG. 9 is the perspective illustration from the bottomside of the inner bag for bag-in-box of FIG. 7 in which liquid is filledup, and FIG. 10 is the perspective illustration from the bottom side ofthe inner bag for bag-in-box of FIG. 8 in which liquid is filled up. Theinner bag for bag-in-box shown in FIG. 9 and FIG. 10 have a weak pointthat the side films near the heat sealed part is easily open and themechanical strength against the inner pressure is not so strong.

[0065] Further, the second invention will be illustrated more readily inaccordance with the drawings.

[0066]FIG. 11 is the plane view of the folded state of the inner bag forbag-in-box of the second invention. In FIG. 11, 17 is the not sealedpart, 2 is the heat sealed part of the upper side, 3 is the heat sealedpart of the lower side, 13 is the heat sealed part of the sideperiphery, 12 and 12′ are the folding line of the side film, 15 is thespout, 4 is the side film and 6 is the front film. In a case of thisinner bag for bag-in-box, when a hand is inserted from the side part, afinger can pass through from the not sealed part 17 and can hold thecorner heat sealed part. Regarding the lower side, it is also possibleto prepare a not sealed part and to seal it.

[0067]FIG. 12 is the plane view of the folded state of the inner bag forbag-in-box of another Example of the present invention. In FIG. 12, 18is a cut out part and 7 is a oblique heat sealed part. When the innerbag is hold by the finger passed through the not sealed part of theinner bag for bag-in-box of FIG. 11, since sometimes the film of notsealed part cuts into the finger, FIG. 12 is the Example to avoid saidproblem and to reduce the load to the finger by preparing a cut out part(handle hole) 18. And, for the purpose to prevent the leak of thecontents in the inner bag from the cut out part (handle hole) 18, a heatsealed part 7 is prepared obliquely from the edge part of the heatsealed part to the outer periphery part. By preparing the cut out part(handle hole) 18, it becomes possible to hold the heat sealed part ofthe upper side easily and certainly without burden.

[0068]FIG. 13 is the plane view of the other Example of the presentinvention, to the lower part of which a oblique heat sealed part 7 isprepared. By preparing the oblique heat sealed part 7 at the lower part,it becomes possible to reduce the amount of remaining liquid in theinner bag at the discharging of the contained liquid in the inner bag.Further, it is possible to prevent the damage of the inner box caused byrubbing of the side surface film at the transferring action of thefilled up inner bags for bag-in-box.

[0069]FIG. 14 is the plane view of the inner bag for bag-in-box fromwhich a triangle shape fin part formed by preparing a oblique heatsealed part at the lower side. And by cutting off said triangle shapefin part, the self-standing ability of the inner bag filled up withliquid is improved.

[0070]FIG. 15 is the perspective view of the inner bag for bag-in-box ofFIG. 14 in which liquid is filled up. It is clearly understand from FIG.15 that the film locating at the both side of the upper heat sealed partcan expand to front and rear direction, and the filled up inner bag canbe easily lifted by inserting fingers into handle holes. If the handlingholes are not prepared, it is not so easy to lift the large capacityinner bag of 20 liter around, because the high load is burdened to thefingers.

[0071] If the laminate which laminate a biaxial orientated film or anylon resin layer which are hard to be adhered by heat sealing arearranged at the surface is used as a side film, a front film and a rearfilm can be sealed by heat and adhered each other without sealing theside film by preparing a punch hole on the side film. FIG. 16 is theplane view of the inner bag for bag-in-box using a laminate arranging aresin layer which is hard to be sealed by heat on the surface as a sidefilm. In FIG. 16, a punch hole is prepared at the corner of the sidefilm, the front film and rear film forms the reinforcing heat sealedpart 16 by being sealed by heat together with without sealing the sidefilm throughout the punch hole, and a cut out part 18 can be preparedbetween a heat sealed part and a corner heat sealed part so as the cutout part acts as a handle.

[0072]FIGS. 17 and 18 are the plane view showing the other examples ofthe present invention. These examples are showing the cases abbreviatingthe sealing of the side part. These bags show the following case, thatis, the both ends of the cylindrical film such as an inflation tube or acylindrical tube formed by back sealing method is folded to inner sideso as to form tucks and upper and lower part are adhered by heatsealing. FIG. 17 shows an example that a handle hole is prepared at theupper triangle shape fin part of the inner bag that abbreviating thepreparation of the sealing at the side part, further another handle holeis also prepared at the lower triangle shape fin part of the inner bag.FIG. 18 shows an example that a reinforcing heat sealed part 16 isprepared by a punch hole closely to the upper corner and a handling holeis prepared at the upper triangle shape fin part, further, the lowertriangle shape fin part is cut off.

[0073] Furthermore, FIGS. 19 and 20 are the partial plane view showingthe other examples of the present invention. FIG. 19 shows an examplethat a reinforcing heat sealed part 16 is prepared by a punch hole atthe corner part and closely to the end of the heat sealed part by makinga punch hole, and FIG. 20 shows an example that a cut out part 18 isprepared between reinforcing heat sealed part 16 prepared by two punchholes shown in FIG. 19. In FIG. 19, since the part between two holes isnot sealed, it is possible to hold the bag for bag-in-box by piercingfingers throughout this not sealed part. As shown in FIG. 20, the bagfor bag-in-box can be hold more easily by preparing a cut out part 18.

EXAMPLES AND COMPARATIVE EXAMPLES

[0074] The first invention will be illustrated in more detail accordingto the Examples, however, not intended to be limited to these Examples.

Example A and B and Comparative Example C and D

[0075] The self-standing test and the dropping test of the container arecarried out on Example A and B of the present invention corresponding toFIG. 2 and FIG. 4 and Comparative Example C and D corresponding to FIG.7 and FIG. 8 which are the conventional type container. Theself-standing ability and the intensity for dropping of these containersare compared. The materials of these inner bag are the double bag usinglinear polyethylene mono film of 60 μm thickness as an inner layer andusing laminated film composed of 15 μm thickness nylon film/60 μmthickness linear polyethylene mono film as an outer layer. The capacityof the inner bag is united to 20 liter.

[0076] The method for self-standing test of the container is illustratedas follows. That is, an inner bag of 20 liter capacity is filled up with20 liter of water is settled without an outer box, then the floor isinclined to the front and rear direction and the right and leftdirection of the inner box. The incline angle of the floor when theinner bag tumbles down is measured. The test is repeated for five times.The results are summarized in Table. 1.

[0077] The method for the dropping test of the container is illustratedas follows. That is, an inner bag of 20 liter capacity is filled up with20 liter of water is fallen down to the floor, and the height that theinner bag is broken and the broken position are measured. The test isrepeated for five times. The results are summarized in Table. 2. TABLE 1Comparison test results of Self-standing ability Inclined angle of floorfor a bag tumbling down 20 liter of water is filled into a bag of 20liter capacity Measuring number: n = 5 inclined angle for the bagtumbling down (degree) specimen front and rear direction right and leftdirection Example A 10˜15 10˜20 Example B 20˜25 20˜25 Comp. Example C10˜15 10˜20 Comp. Example D 20˜25 20˜25

[0078] TABLE 2 Comparison test results of the dropping test Height forbreaking 20 liter of water is filled into a bag of 20 liter capacityDropped down from the bottom surface measuring Temp.: 20° C., Measuringnumber: n = 5 height for bag breaking specimen (m) broken position ofbag Example A 1.0˜1.5 bottom crossing point Example B 0.8˜1.2 bottomcrossing point Comp. Example C 0.5˜0.7 bottom crossing point Comp.Example D 0.3˜0.5 bottom crossing point

[0079] According to these test results, following facts are becomeclear. That is, from the results of Table 1, it is clearly understoodthat the self-standing ability of Examples A and B are not spoiled incomparison with that of Comparative Examples C and D. Further, from theresults of Table 2, the inner bag of Comparative Examples C and D breaksat lower height than that of Examples A and B, and the breaking positionis the crossing position of lower heat sealed part and side film.Therefore, it is obvious that the intensity for dropping of Examples Aand B are superior to that of Comparative Examples C and D.

[0080] Possibility for the Industrial Use

[0081] As mentioned above, in the inner bag for bag-in-box of gazetteshape, the first invention is an inner bag for bag-in-box comprisingreinforcing heat sealed parts formed by cutting out side films andsealing a front film with a rear film are provided continuously orclosely to heat sealed parts on an upper side and/or a lower side of theinner bag. And according to the first invention, when abnormal stresscaused by careless falling down of the inner bag is loaded to the bag,it is possible to prevent the breaking of the side films near the heatsealed part on an upper side or a lower side and can reduce the load tothe top heat sealed part without spoiling the self-standing ability ofthe container, that is the substantial mechanical strength of the bagcan be improved.

[0082] According to the present invention, at the corner part or nearthe corner part, side films are cut off and a front film is adhered byheat sealing with a rear film, and by this structural feature, thedamage of a side film caused by the contact with the inner surface of anouter box can be prevented. And, since the heat sealed parts at thecorner part can be used as the handling part, it is convenience forloading and unloading of the filled up inner bag from the outer box,transferring of the filled up inner bag or for discharging of thecontents contained in the inner box.

[0083] Further, although the upper fin part does not have influence onthe self-standing ability of the inner box directly, it is possible tobe cut off as well as the lower fin part so as to improve theself-standing ability by making the center of gravity lower, or not tobe cut off so as to be used as a handle part when the bag is handled.Furthermore, it is possible to prepare a partial heat sealed part or afull heat sealed part.

[0084] According to the second invention, by preparing a not sealed partor a cut out part at upper and/or lower side, the heat sealed part inthe corner part can be used as a handle part, consequently it bringsexcellent effects such as easy work, good handling and convenience incases when a filled up inner bag is lifted without an outer box,transferred or the contained liquid is discharged.

1. A gazette shape inner bag for bag-in-box whose side film to be foldedis composed of a laminated film prepared by laminating multi layers soas a resin layer which is hard to be adhered by heat sealing is arrangedat the surface, comprising reinforcing heat sealed parts formed bycutting out side films and sealing a front film with a rear film areprovided continuously or closely to heat sealed parts on an upper sideand/or a lower side of the inner bag.
 2. The inner bag for bag-in-box ofclaim 1, wherein the front film is adhered by heat sealing with the rearfilm by cutting out the side film at a corner part or near the cornerpart.
 3. The inner bag for bag-in-box in accordance with claim 1 orclaim 2, wherein said inner bag possesses a fin part of triangle shapewhich is divided from a containing part by a heat sealed part.
 4. Theinner bag for bag-in-box of claim 3, wherein at least one fin part iscut off.
 5. The inner bag for bag-in-box of claim 4, wherein all finparts locating at the lower side are cut off.
 6. A gazette shape innerbag for bag-in-box prepared by adhering by heat sealing of one or moresheets of film, wherein said inner bag possessing a holding part formedby sealing the front film with the rear film through or without throughthe side film so that a not sealed part between the films is formed ator near at least one corner part between the films and the heat sealedparts and so that, when a hand is accessed from the side part of theinner bag, fingers are passed to the outside of the inner bag throughthe not sealed part.
 7. The inner bag for bag-in-box of claim 6, whereinthe holding part is prepared on both side of the heat sealed partlocates at upper and/or lower side.
 8. The inner bag for bag-in-box inaccordance with claim 6 or claim 7, wherein said inner bag possesses acut out part prepared by cutting off one part or all part of film of thenot sealed part locating at upper and/or lower side.
 9. The inner bagfor bag-in-box in accordance with any one of claims 6 to 8, wherein saidinner bag possesses a fin part divided by triangle shape, further theholding part is formed on said fin part.
 10. The inner bag forbag-in-box of claim 9, wherein all fin parts locating at the lower sideare cut off.
 11. The inner bag for bag-in-box in accordance with any oneof claims 6 to 10, wherein the side film is the laminate which laminateso as resin layer which are hard to be adhered by heat sealing to bearranged at the surface, and the holding part is prepared by sealingwithout sealing the side film by preparing a punch hole on the sidefilm.